The present system relates to electrical devices, and more particularly, to leads for use in medical procedures.
Electrosurgical techniques are used in both open and minimally invasive surgical procedures. In such techniques, high frequency electric current is applied to biological tissue as a means to cut, coagulate, desiccate, or fulgurate tissue. Electrosurgical techniques are beneficial because the techniques include the ability to make precise cuts with limited blood loss. More specifically, electrosurgery employs 0.5-2 MHz (alternating) radiofrequency current applied to a small area (active) electrode.
Generally, electrosurgical instruments are of two types: monopolar and bipolar. A monopolar electrosurgical system includes an instrument comprising an electrode that is conductively connected to the active terminal of a monopolar RF generator. Monopolar electrosurgical instruments are used primarily for electrosurgical cutting of tissue and provide for generally wide-reaching coagulation. Bipolar electrosurgical systems, on the other hand, include instruments which have both positive and negative electrodes on the instrument itself, which electrodes are connected to the positive and negative terminals of a bipolar RF generator. Bipolar electrosurgical instruments generally provide the physician with greater control of the path of the RF energy through the patient, as the RF energy generally passes only though the tissue located between the electrodes of opposite polarity on the instrument, and not otherwise through the patient's body. Thus, bipolar electrosurgical instruments may provide for a more refined surgical technique and more predictable current flow.
Bipolar electrosurgical instruments, e.g., endoscopic accessories, must have the ability to connect to a standard electrosurgical unit (ESU). Depending on the specific unit, this connection can be a mono plug or a dual plug. See, for example, BCP-7A (dual plug) and BCP-7B (mono plug) Quicksilver Bipolar® Probes (supplied by Cook Medical, Bloomington, Ind. 47402). The connection points for a dual plug on ESUs are a fixed distance from one another.
Because of the nature of dual plugs, too much slack between the leads leaves the opportunity for the end user to incorrectly connect the bipolar device to the ESU or other nearby unit, thus posing a risk to user or patient, or causing device malfunction. To avoid this type of misconnection, the leads on the bipolar device can simply be fixed a set distance from one another to adequately mate to the fixed distance connection point on the ESU. More particularly, safety requirements for the use of high frequency surgical equipment dictate that active connectors having more than one pin shall have fixed pin spacing, and that “flying” leads are prohibited. Fixed is defined in these requirements as meaning fastened or otherwise secured at a specific location either permanently or so that it can only be detached by means of a tool, i.e., making removal or opening difficult without using a tool.
However, different ESUs have different set distances of connection points, thus requiring different lead devices depending on the distance of the connection points on a particular ESU. A need therefore exists for devices that provide variable fixed leads so as to be compatible with ESUs that may have varying lead distances.